Screening of salt tolerant transgenic and non-transgenic cotton varieties under various levels of NaCl induced salinity stress

摘要

Salinity induced stress is one of major hurdle for crop production that significantly decreased crops yield. Higher levels of salts reduced the uptake of water, osmotic imbalance, poor germination and restriction of cell division. However, crops varieties that are tolerant towards salts accumulation can grow better under salinity stress. As cotton is moderately salt tolerant and major cash crop, therefore current study was conducted to screen salt tolerant cotton BT and non-BT varieties. For experiment, five BT (CIM616, CIM598, CIM179, CIM602 and GH-Mubarik) and non-BT cotton varieties (Cyto124, CIM554, CIM573, CIM620 and Lalazar) were grown under various levels (0, 50, 100, 150, 200 and 250 mM) of artificially NaCl induced salt stress. NaCl induced salinity stress, 250 mM level was more severe, that reduced shoot and root length, shoot and root fresh and dry weight, owing to decrease in chlorophyll a, chlorophyll b and total chlorophyll. A significant improvement in shoot length, root length, shoot fresh weight, root fresh weight, shoot dry weight and root dry weight confirmed the potential of BT CIM598, CIM602, non-BT Cyto124 and CIM620 varieties to withstand against salt induced stress. Furthermore, an improvement in chlorophyll a, chlorophyll b and total chlorophyll and less electrolyte leakage validated the potential of BT CIM598, CIM602, non-BT Cyto124 and CIM620 as salt tolerant cotton varieties. In conclusion, BT CIM598, CIM602 and non-BT Cyto124, CIM620 cotton varieties have the potential to grow better at seedling stage under salinity stress.